In the 1960's Dr. Paul Kopsch (an Ohio coroner),
Daniel Turcos (a police sergeant) and Donald Ward (Dr. Kopsch's special
investigator), began experimenting with special purpose handgun ammunition.
Their objective was to develop a law enforcement round capable of improved
penetration against hard targets, such as windshield glass and automobile
doors. Conventional bullets, made primarily from lead, often become deformed
and ineffective after striking hard targets, especially when fired at handgun
velocities.

After some experimentation with steel rounds, the officers settled on a
brass core with a 'lubricating' jacket of
Teflon. Although a myth persists that the Teflon is there to either penetrate
"bullet-proof" vests more effectively, or protect the bore of the
firearm that fires it, Dr. Kopsch himself has testified that the Teflon
actually reduces these bullets' penetration in Kevlar, and is only there to
reduce the likelihood of ricochets. (Kopsch, Turcus, & Ward struck upon the
idea of the Teflon coating after finding out that the manufacturers of canes
impregnate the plastic tips of their canes with a Teflon compound; under
pressure, the Teflon actually helps the bullet to "stick"
momentarily, and it is this characteristic that reduces the chances of a
ricochet off of the glass or metal surfaces of an automobile). The inventors
named the round the 'KTW Bullet,' after their initials.(1)

This round
was headstamped: KTW 9MM LUGER

Note the 2
driving bands on the brass projectile.

Lew Curtis, and advanced collector of 9mm ammunition notes:(2)

I was in Ohio when they put on their first display at the Ohio Gun Collectors show in Columbus and I spoke to one of them who was at their table. They had just started production and their big pitch at the time is that their 357 magnum shot at the back of a fleeing car would penetrate the entire car and crack the engine block stopping the car. They had photos of cars they had shot. I was a 1st Lt at the time and was impressed. I left Ohio and went back to SEA in early 1969 so this must have been 1968 they introduced the KTW ammo and began selling it because I bought a box. The cases were all reloads. In the 1970s they introduced their own headstamp. The initial production was all a steel alloy (weakly magnetic) and the name was something like Kennetite or similar I think. It was significantly later, 1981 in one source (http://www.guncite.com/gun_control_gcgvcopk.html), that the brass bullet was introduced. I think this must have been in the same time frame they left Lorain Ohio and became:
NORTH AMERICAN ORDNANCE CORPORATION, Pontiac, Mighigan 48057, U.S.A.

[It is important to note...] that both a magnetic alloy bullet and later a brass bullet were produced and sold.

NOTE: Serious restrictions were placed on this ammunition by Congress after a hysterical campaign by gun control extremists branding these as "cop killer bullets".

References:

(1) Wikipedia.com

(2) email from Lew Curtis to webmaster November 26, 2006.

Copyright 2006 by the International Ammunition Association,
Inc. All rights reserved.